Initiatives on Regulation of Transmission Media
Between Smart Meters and HEMS
Takefumi Yamazaki

Senior Research Engineer,Supervisor
NTT Service Evolution Laboratories

1. Introduction
Concern for managing the supply and demand for electrical
power increased in the wake of the Great East Japan Earthquake
in 2011, and with the increased awareness and demand in society
to install and spread use of smart meters—electricity meters
incorporating a communications function—in society, related
initiatives are becoming more active. The government-initiatedJapan Smart Community Alliance ( JSCA), established in2010 to unite the government and citizens in advancing smart
communities, created the Smart House/Building Standardization
and Business Development Forum. To promote the spread ofsmart meters and related services, The Forum has defined theECHONET Lite[1] standard interface between Home Energy
Management Systems (HEMS) and eight types of key devices,
including smart meters (the others are air conditioners, lighting,solar power panels, storage batteries, EV/PHV, fuel cells, and hot
water heaters).
This paper introduces initiatives for regulating the transmission
media and interconnectivity issues when using ECHONET■ Figure 1: Lower layers of ECHONET Lite

14

New Breeze Spring 2015

Lite as the communication interface between smart meters andHEMS.

2. Issues with regulation of transmission
media for ECHONET Lite
ECHONET Lite is a communications standard set by
the ECONET Consortium[2], a standardization organization
comprising manufacturers of HEMS-related electronics,communications providers, and power companies. It describes
in detail, the states and control commands for more than 90
types of HEMS-related devices. ECHONET Lite definescommunications protocols and device objects corresponding tolayers 5 to 7 of the OSI model (the upper layers), but does notdefine layers 4 and below. Since various media could be used
for transport, maintaining interconnectivity at the transmission
level has been an issue. The lower levels for ECHONET Liteare shown in Figure 1. To implement interconnectivity between
ECHONET Lite devices from different device manufacturers,
it is very important that they adopt and implement a well-known■ Figure 2: Overview of protocol stacks for ECHONET Lite lower communication layers

standard communication format and not their own originalformat.

3. Regulation of ECHONET Lite lower
communication layers at the TTC
Considering the above issues, the TTC Next-generation
Home Network System Expert’s Committee has created technicaland standardization documents[3][4] defining various standards for
the ECHONET Lite lower communication layers. An overviewof documents related to the standard is given below.

3.1 TR-1043 Home Network Communication Interface
Implementation Guidelines
This technica l document [5] specif ies wel l-k now ncommunications formats and protocol stacks for the lower
communication layers of ECHONET Lite. An overview of theseprotocol stacks is shown in Figure 2.
The document also gives a network model with configurationsof how smart meters and other HEMS related devices
are connected to a home network and describes a physicalconfiguration example based on the model. The physicalconfiguration example is shown in Figure 3.

■ Figure 3: Example physical configuration

New Breeze Spring 201515

3.2 JJ-300.10 Home Network Communication Interface for
ECHONET Lite (IEEE 802.15.4/4g/4e 920 MHz band)
This standard document [6] describes communication
format specifications for the physical, data-link, network, andtransport layers when using 920 MHz band radio as the lower
layer communications environment for ECHONET Lite. Thecommunication specification protocol stacks specified in JJ-300.10
and related standardization organizations are shown in Figure 4.
JJ-300.10 describes three modes: A, B, and C. For modes
A and C, it describes the Wi-SUN specification defined by theWi-SUN Alliance as the Route B connection format, along withparameters, and security specifications. For mode B it describes
the ZigBee IP specification defined by the ZigBee Alliance.
3.3 JJ-300.11 Home Network Communication Interface forECHONET Lite (ITU-T G.9903 Narrow band OFDMPLC)
This standardization document[7] describes communication
formats for the physical, data-link, network, and transport layers
when using power lines for the lower-layer communication
with ECHONET Lite. The protocol stack for communication■ Figure 4: Overview of JJ-300-10■ Figure 5: Overview of JJ-300-11

16

New Breeze Spring 2015

specifications in JJ-300.11 is shown in Figure 5.
3.4 TR-1052 HEMS-Smart Meter (Route B)
Communication Interface Detailed Implementation
Guidelines
This technical document[8] defines the required authentication
methods and connection sequences in detail for each of theHEMS-Smart meter (Route B) transport media. Specifically, acommon authentication ID and password format are specified
for the Route B connection so that the same authentication canbe used regardless of the selected transport medium. The Route
B authentication ID and password usage and detailed connection
sequence are also described for JJ-300.10v2 mode A (Wi-SUN IP)
and JJ-300.11.v2 (G3-PLC), and JJ-300.10v2 mode B (ZigBee IP).

4. HEMS-Smart Meter Route B
Communication Format Operational
Guidelines and state of adoption at variouspower companies
JSCA is creating the “HEMS-Smart meter Route B
Communication Format and Operating Guidelines”[9], describing

■ Figure 6: Basic diagram of well-known standard media protocol stack for HEMS

agreed-upon common items for opening and operating RouteB communications between smart meters and HEMS, so thatthese connections can operate properly. The guidelines describe
the transmission media, communication formats and network
structure with reference to the TTC technical documents
introduced in Section 3. The protocol stack described in theseguidelines is shown in Figure 6.
The Route B communication formats adopted by each powercompany are also shown in Figure 7, with JJ-300.10 Mode A(Wi-SUN IP) as the main format, and JJ-300.11 (G3-PLC) as thecomplementary format, according to the operational guidelines
above.

5. Conclusion
We have introduced TTC standardization activities fortransport media, as necessary to guarantee interconnectivity ofdevices using ECHONET Lite, which is the standard protocol
used between smart meters and HEMS. Standardization of thecommunications interface between smart meters and HEMS
is a key component of using smart meters effectively, andimplementation of the standard specifications that include thesetransport media will be very significant for the proliferation andutilization of smart meters.
In the future, as ECHONET Lite is incorporated into variousdevices, it will be necessary to support new communications
standards, and the standardization and technical documents willneed to be revised to ensure interconnectivity. As such, the rolethat the TTC and others will need to play will continue to besignificant.
Drafts of the TTC standardization and technical documents
discussed here were discussed at the New Generation Network
Promotion Forum, IP Network Working Group, Residential
ICT Strategic Working Group (lead by Prof. Yasuo Tan [JAIST/NICT]), and went through deliberation in the Next Generation
Home Network Systems Experts Committee before being
settled. We would like to express our sincere gratitude to all those
involved.

References[1] ECHONET Lite, http: http://www.echonet.gr.jp/english/index.htm[2] ECHONET Consortium, http://www.echonet.gr.jp/[3] ITU Journal, “Trends in standardization of communication protocols on home networks in
the HEMS field,” Vol. 43, No. 11, 2013-11[4] TTC REPORT, Next generation home network systems experts committee (TR-1051,TR1052,TR-1053), Vol.29/No.2 2014-7[5] TTC Technical Report: TR-1043 Home network communication interface implementationguidelines[6] TTC Standard, JJ-300.10 Home network communication interface for ECHONET Lite(IEEE802.15.4/4g/4e 920 MHz band)[7] TTC Standard, JJ-300.11 Home network communication interface for ECHONET Lite (ITU-TG.9903 narrow band OFDM PLC)
[8] TTC Technical Report: TR-1052 HEMS-Smart meter (Route B) communication interface
detailed implementation guidelines[9] JSCA Smart house/building standards/business promotion forum, Reference #3: HEMSSmart meter Route B operating guidelines, 1st Ed. (2013-05), 2nd Ed. (2014-12)■ Figure 7: Route B communications at various powercompanies
RFP status for communication and related systems (Route B) at
each power company
Communication formats for routes selected by each power company(as of Sept. 2014)
Main format

Complementaryformat

Hokkaido ElectricPower Company

920 MHz band radio(Wi-SUN format (IP)

PLC
(G3-PLC format)

Tohoku ElectricPower Company

920 MHz band radio(Wi-SUN format (IP)

PLC
(G3-PLC format)

Tokyo ElectricPower Company

920 MHz band radio(Wi-SUN format (IP)

PLC
(G3-PLC format)

Chubu ElectricPower Company

920 MHz band radio(Wi-SUN format (IP)

PLC
(G3-PLC format)

Hokuriku ElectricPower Company

920 MHz band radio(Wi-SUN format (IP)

PLC
(G3-PLC format)

The Kansai ElectricPower Company

920 MHz band radio(Wi-SUN format (IP)PLC
G3-PLC format)

The Chugoku ElectricPower Company

920 MHz band radio(Wi-SUN format (IP)

PLC
(G3-PLC format)

Shikoku ElectricPower Company

920 MHz band radio(Wi-SUN format (IP)

PLC
(G3-PLC format)

Kyushu ElectricPower Company

920 MHz band radio(Wi-SUN format (IP)

PLC
(G3-PLC format)

The Okinawa ElectricPower Company

920 MHz band radio ](Wi-SUN format (IP)

PLC
(G3-PLC format)* Each company in principle considers installing the “Main format”, but selects the“Complementary format” when environmental or other conditions make this difficult.

New Breeze Spring 201517